A lot of small business owners already plan their posts in ChatGPT. The plan is often good. Then comes the part nobody talks about: thirty posts sit in a chat window, and you copy them one at a time into Instagram, then Facebook, then LinkedIn, fixing the line breaks as you go. That takes longer than the planning did.
This guide has two halves. First, the prompts that get you a month of posts you would publish. Then how to connect ChatGPT to Postfjord so it reads your brand voice and your calendar, and writes the posts straight into it as drafts. Claude works the same way, and on more plans, so it gets its own section.
Our example is a small bakery in Portland, Oregon, planning November 2026. Swap in your own business as you read.
Why ChatGPT is where people start
Most people you know have tried it. By the end of July 2025, ChatGPT had more than 700 million weekly users, according to How People Use ChatGPT, a working paper by OpenAI's research team and Harvard economist David Deming. OpenAI has since said it has more than 900 million weekly users.
| Label | Value |
|---|---|
| Nov 2023 | 100 million |
| Nov 2024 | 350 million |
| Jul 2025 | 700 million |
The paper gives the first two as "more than 100 million" after one year and "almost 350 million" after two. The same study sorted 1.5 million conversations by what people wanted. About 40% of messages were "doing": drafting text, planning, producing something. Writing was the most common task at work, at about 40% of work messages.
So planning posts in ChatGPT is a normal thing to do. The trouble starts after the plan.
Step 1: give ChatGPT the facts it cannot guess
A month plan fails when ChatGPT fills the gaps with guesses. It does not know your prices, your hours or what you sold out of last Saturday. Start every planning chat with a short brief. Here is the bakery's:
We are Rose Street Bakery in Portland, Oregon. Sourdough, pastries and coffee, open Tuesday to Sunday, 7 to 3. Our customers are neighbors who walk over on weekend mornings, and office workers who order pie boxes before holidays. We post on Instagram and Facebook. Our voice is warm, short and a little dry. We never use more than two emoji. Pie preorders for Thanksgiving open November 2 and close November 22. Pickup is Wednesday, November 25. We are closed Thanksgiving Day.
Five facts do most of the work: what you sell, who buys it, where you post, how you sound, and the dates that matter this month. The dates matter most. A plan without them gives you thirty nice posts about bread and none about the preorder that pays for December.
For more on what a brief needs, see Five tips for a brief Claude can write a good post from.
Step 2: ask for the skeleton before the posts
Do not ask for thirty finished posts in one go. You get thirty posts that sound the same, and it is hard to fix a month when you have to read all of it. Ask for the plan first:
Plan November 2026 for us: 3 posts a week on Instagram and Facebook, Tuesday, Thursday and Saturday. Give me a table with date, content pillar, topic and format (photo, carousel or Reel). Use these pillars: behind the scenes, product, customers, holidays. No more than one sales post in a row.
A table is easy to scan. You see at a glance that week three has two Reels in a row, or that nothing points to the preorder deadline. Fix it in the chat:
Move the preorder reminder to Friday, November 20, two days before orders close. Add a post on Saturday, November 28 for Small Business Saturday.
Step 3: write the posts one week at a time
Once the skeleton is right, ask for the text:
Write the posts for week 1 (November 3 to 7). For each: a first line that works on its own in the feed, 40 to 80 words, a question or a clear next step at the end, and 3 to 5 hashtags. Write an Instagram and a Facebook version where they should differ.
A week at a time keeps each answer short enough to read closely. Mark what you like and say why:
Posts 1 and 3 are right. Post 2 sounds like an ad. Rewrite it the way you would tell a regular at the counter.
ChatGPT uses that note for the rest of the chat, so later weeks need fewer fixes.
Step 4: the copy and paste problem
This is where most months stall. You have twelve posts across four replies, each with two versions, and each needs a date, an image and a channel. By hand that is twenty-four trips between tabs. Line breaks break, the hashtags land in the wrong version, and the Thursday post goes out on Friday because you were busy on Thursday.
A scheduler fixes the "busy on Thursday" part. Connecting ChatGPT to the scheduler fixes the rest.
Step 5: connect ChatGPT to Postfjord
Postfjord runs an MCP server, the open standard AI apps use to reach other tools. When ChatGPT is connected, it can do what you would do in the app:
- Read your brand voice: tone, audience, do and don't rules, content pillars, preferred hashtags and your example posts. See Brand voice.
- Read your calendar: what is scheduled, what is a draft, where the gaps are.
- Read your numbers: followers, likes and comments, top posts and the best times to post.
- Create drafts: one post per idea, with the text for each channel, in your calendar.
With that, Step 1 gets shorter. ChatGPT reads the brief from your brand profile, so you stop pasting it into every chat.
What you need
Two things, and the first is the one to check before you start.
A ChatGPT plan that allows custom connectors with write actions. OpenAI's help page Developer mode and MCP apps in ChatGPT (checked September 28, 2026) says:
- Business, Enterprise and Edu: full MCP support, including actions that write, is rolling out in beta. On Business, only admins and owners can turn on developer mode and add an app. It works on ChatGPT on the web, not in the mobile apps.
- Pro: developer mode can connect an MCP server with read and fetch permissions only. ChatGPT can read your brand voice and calendar, but cannot create drafts.
- Free, Go and Plus: the page does not list them for developer mode or custom MCP apps.
OpenAI's page on creating GPTs (checked the same day) also says personal accounts, including Free, Go, Plus and Pro, can no longer create new custom GPTs, so that older workaround is closed for new setups. OpenAI changes these pages often. Check them before you pay for an upgrade.
A Postfjord plan with the API. The MCP server is included from the Solo plan, $39 a month or $29 a month paid yearly, and only the workspace owner can connect an app. See Pricing.
The setup, on ChatGPT Business
- In ChatGPT on the web, turn on developer mode. On Business it is under your settings, Apps, Advanced settings, or when you create an app from the workspace settings under Apps, Create.
- Create a new app. Name it Postfjord, paste
https://app.postfjord.com/api/mcpas the MCP server URL and choose OAuth as the sign-in. - ChatGPT sends you to Postfjord. Sign in, pick the workspace, choose what ChatGPT may do, and press Allow.
- Start a new chat and pick Postfjord from the tools menu.
For step 3, choose Drafts only when you start. ChatGPT can then create and edit drafts, but a draft can never get a date, so nothing goes out until you schedule it yourself in Postfjord. You can connect again with a higher level later. The levels are described in the MCP help page.
The connection shows up in Postfjord under Settings, Apps, Your keys, named after ChatGPT. Remove it there and ChatGPT is disconnected at once.
Step 6: the prompts, once connected
Now the month plan becomes a conversation with your calendar open. These are the prompts the bakery would use for November:
Read our brand profile and our November calendar. What is already planned, and where are the gaps?
Plan the rest of November from our content pillars. 3 posts a week, Tuesday, Thursday and Saturday. Show me the plan as a table first.
Look at our top posts from the last 90 days. What do they have in common? Use that in the November plan.
The plan is good. Create week 1 as drafts in Postfjord, for Instagram and Facebook, in our voice.
Create a draft for Friday, November 20: last call for Thanksgiving pie preorders, orders close Sunday.
ChatGPT may ask you to confirm before it creates anything. OpenAI's page says it asks based on the app's permissions and the action. Say yes, and the drafts appear in the Postfjord calendar.
Then you do the part AI should not do alone. Open each draft, add the photo from your media library, read it aloud, and schedule it. Postfjord publishes it at the time you set. If a post fails, the calendar shows which one and the reason.
The other option: Claude
Claude connects to Postfjord the same way, with a sign-in and no key, and on more plans. Anthropic's help page Get started with custom connectors using remote MCP (checked September 28, 2026) says custom connectors work on Free, Pro, Max, Team and Enterprise. Free is limited to one custom connector.
- In Claude, open Settings, then Connectors, and press Add custom connector.
- Name it Postfjord and paste
https://app.postfjord.com/api/mcp. Press Add, then Connect. - Sign in to Postfjord, pick the workspace and what Claude may do, and press Allow.
The prompts from Step 6 work unchanged. The connector is shared by claude.ai and the Claude apps on your computer and phone, so you can ask for a draft from your phone between two customers.
If you are on ChatGPT Plus, this is the honest route to a month plan without copy and paste: keep ChatGPT for brainstorming if you like it, and connect Claude to create the drafts.
Or skip the outside app
Postfjord's own AI runs on Claude and is included in your plan, Free too, within the plan's AI budget. In the calendar, Plan next week reads your brand voice, content pillars and what has worked before, and proposes a week of posts. You edit, remove or keep each one, then apply the rest as drafts or scheduled posts. See Calendar and the AI composer.
The connector is worth it when you already spend your day in ChatGPT or Claude and want the planning to happen there, with your other chats, files and notes.
The monthly routine
Here is the whole routine, for the last week of each month:
- Update your brand profile in Postfjord with next month's dates: offers, holidays, closures.
- In ChatGPT or Claude, ask what is planned and where the gaps are.
- Ask for the skeleton as a table and fix it in the chat.
- Create the drafts one week at a time, and correct the voice on week one.
- In Postfjord, add photos, read each post aloud and schedule it.
The bakery's November comes to 13 posts on two channels. Most of your time goes into step 5, choosing photos.
FAQ
Which ChatGPT plans can connect to Postfjord?
According to OpenAI's developer mode page, checked September 28, 2026: Business, Enterprise and Edu can add a custom MCP app that creates drafts, on ChatGPT on the web. Pro can connect with read permissions only. The page does not list Free, Go or Plus.
Can ChatGPT publish posts without me?
Only if you allow it. When you connect, you choose what ChatGPT may do. With Drafts only, it can create and edit drafts but cannot give them a date or publish them. Nothing leaves Postfjord until you schedule it.
Does it cost extra in Postfjord?
No. The MCP server is included from the Solo plan. If you ask ChatGPT to use Postfjord's own composer, those drafts count against your workspace AI budget, like drafts written in the app. Text that ChatGPT writes itself does not.
Is ChatGPT or Claude better for planning posts?
Both write good posts from a good brief. The difference for this setup is access: Claude allows a custom connector on its Free plan, while ChatGPT needs Business, Enterprise or Edu to create drafts. Use the one you already pay for, and try the other if it does not have the connector.
Can I connect more than one workspace?
Yes. Each connection belongs to one workspace, the one you pick when you sign in. An agency with five clients connects once per client, so each client's drafts land in that client's calendar. See Workspaces and members.
How do I disconnect ChatGPT?
In Postfjord, open Settings, Apps, Your keys, and remove the key named after ChatGPT. It stops working at once.